How many significant figures are there in the following numbers?
(i) `67.8+-0.3` (ii) `4.899xx10^(9)` (iii) `3.56xx10^(-6)` (iv) 0.0065

Explanation

To determine the number of significant figures in each of the given numbers, we will analyze them one by one.

### Step-by-Step Solution:

**(i) `67.8 ± 0.3`**
1. Identify the digits in the number `67.8`.
2. All non-zero digits are significant. Here, `6`, `7`, and `8` are non-zero digits.
3. Therefore, the significant figures in `67.8` are 3 (i.e., `6`, `7`, and `8`).
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